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A. POTDEVIN BAG Filed NOV. 17, 1936 ATToRN Ys May 31, 193s.

` Patented May 31, 193s UNITED s'rA'rl-:s

BAG

Adolph muevan, Garden city, N. Y., signor tu Potdevin Machine Company, Brooklyn, N. Y., a corporation oi.' New York Application November 17, 1936, SeriallNo. 111,189

1 Claim.

, This invention relates to improvements in valve bags and to the method of making the same.

Cue of the objects of the present invention is the provision of a valve bag in which one end of the bag tubing is' formed in a novel manner so that when the tubingis folded inwardly at one edge of the bag a new and improved form of valve is provided.

A further object of this invention is the provision of a valve bag, the valve of which is so shaped that perfect functioning of the valve is assured, the valve or valve ilap being so formed that the valve will adjust itself more uniformly to the contour of the inside of the filled bag than is possible with prior structures.

My invention has for a further object the provisionA of a construction in which a saving in material is effected, this being of material importance, particularly in the case of multi-wall bags.

Qther objects of my present invention will be manifest from the following description and the accompanying drawing. in which:

Fig. 1 is a plan view illustrating the manner in which the bag tubing is divided into bag lengths;

Fig. 2 is a plan view showing a preliminary step in forming the valve and closing the valve end of the bag:

Fig. 3 is a view showing the valve end of the bag in closed position;

.Flg. 4 is a view on line 5 5 of Fig. l3: and

l Fig. 5 is a view on line -l of Fig. 3.

Referring to the drawing in detail: 2 desig' nates the bag tubing which is to be severed into bag lengths 4 in accordance with my invention.

The tubing is severed transversely along :lines 6. These lines of severance are a distinct departure from the straight line oi severance of prior practice. The line of severance t in the upper wall of the tubing begins at one. edge of the tubing with a short straight transverse 'eut Il,l the cut then curving inwardly as shown at I2 and from thence extending in a straight transverse line il to Il adjacent the other edge of the tube, where it curves outwardly as indicated at i8.

The lower wall of the tubing has a short trans.

verse cut corresponding to cut i0 in the upper Awall. This rcut is then curved outwardly as shown at 20, and then continues in a straight 5o transverse cut 22 parallel to the straight cut I4.

'Ihis straight cut 22 merges in the upper wall. into a curve adjacent the opposite edge of the tubing which corresponds to the curved cut Il in the upper wall.

, 65 It is the curved cut il in the upper wall of the tubing and the corresponding curved cut in the or'. filling en d of which is convex.

llower wall which provides the novel flap of the invention.

It will be appreciated that the parallel cuts il and 22 are oifset with respect to each other.

It will be seen from Fig. 1 that a slit 28 is 5 provided in the valve end of the bag length, at the side opposite the valve flap. to facilitate bottoming of the bag. There is no slit. however, at the opposite side or valve side of the bag length so that all of the material at this corner of the 10 bag length is available for valve flap purposes.

-When the bag lengths have been`severed from the tubing the ends are opened up and the lower wall lll and upper wall 32 folded back upon themselves as illustrated in Fig. 2, the corner 34 folded 15 inwardly and the valve corner 36. Paste or adhesive is then applied as shown, and the upper wall 32 folded down along the line 38, and the lower wall 30 folded over upon it along the line v l0. The finished bottom is shown in Fig, 3. It 20 will be seen from this drawing that by omitting the slits at the valve side of the bag length this 'entire corner is available for valve flap purpos.

It will be seen also that this gives a different appearance to this corner of the bag bottom, so that the valve corner is readily distinguishable. 25

It will be appreciated that by curving-the inner end of the valvevflap as shown at Il in Fig. 2, the valve will readily conform to the interior of the bag bottom. f 30 It will be appreciated, furthermore, that with each bag length there is a saving in material as compared with bag lengths made by so cutting through the bag tubing that both walls of the bag length are' of the same length equal-to the space between the end Il of the upper wall and the end 22 of the lower wall of the bag length. This amounts to about to 3A" in a 3" bottom. Itis to be understood that various changesI and modifications may be made in the method of pro- 40 ducing my,improved bag as well as in the bag lt-V selt without departing from the spirit and scope of my invention.

What I claim is:` v I As an article of manufacture. a bag length, 45 one wall of which at one end of the bag length projects throughout the major portion of the width of the bag length beyond the other wall. both walls adjacent one edge of the bag length at the said end of the bag lengthbelng curved outwardly, this curved portion being turned inwardly transversely of the bag length between the walls of the bag length to provide a valve flap, the open v ADoLPn 

